How is BMI calculated?

BMI = weight (kg) / height (m)². Or (weight in lb / height in in²) × 703.

What is a healthy BMI?

18.5–24.9 is generally considered normal. Under 18.5 underweight, 25–29.9 overweight, 30+ obese.

Calculate Body Mass Index from weight and height. Metric (kg, cm) or imperial (lb, in).

Weight (kg)

Height (cm)

How is BMI calculated?: BMI = weight (kg) / height (m)². Or (weight in lb / height in in²) × 703.
What is a healthy BMI?: 18.5–24.9 is generally considered normal. Under 18.5 underweight, 25–29.9 overweight, 30+ obese.

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